I'm not sure if all of this matches up or not. Can you guys please help me? I'm not sure if I need a more powerful amp and more wattage to the headunit. If I do, can you look for the upgrade on www.onlinecarstereo.com ? I'm trying to keep it all as one package.

I need a capacitor as well, but have no idea what to get.
I don't want my battery running out while I'm driving.